#include <unistd.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>



int main()
{

	int sculltest;
	int code;
	
	if ((sculltest = open("/dev/singleUID",O_WRONLY ))<0) {
		printf("open singleUID error! code=%d \n",sculltest);
 		exit(1);
	}
		if ((code=write(sculltest , NULL , 0)) < 0 ) printf("write error! code=%d \n",code);
		else   printf("write ok! code=%d \n",code);

	close(sculltest);

  exit(0);
}
